Micro magnetic silicone elastomer membrane actuator

We present results of the design, fabrication, and testing of a microfabric ated, membrane-type magnetic actuator. Magnetic pieces made of electroplate d Permalloy (Ni80Fe20) are embedded in a thin flexible membrane made of sil icone elastomer. When an external magnetic field is applied, a torque gener ated on the magnetic pieces produces membrane displacement. Permalloy piece s that are 100-mum-wide, 870-mum-long, and 22-mum-thick are strategically p ositioned in a 2-mm-square, 40-mum-thick polydimethylsiloxane (PDMS) membra ne (Sylgard 184). This design, produced through numerical simulations, is o ptimized to realize large membrane displacements. Tests performed on this m embrane actuator showed displacements >80 mum in the presence of a 2.85 x 1 0(5) A/m external magnetic field. Larger displacements are possible with gr eater magnetization fields. This type of membrane actuator can be applied t o the fabrication of tetherless micropumps for use in microfluidic systems. (C) 2001 Elsevier Science B.V. All rights reserved.